simple sugar vs pentose

simple sugar and pentose both are nouns.

Word	Noun	Adjective	Verb	Adverb
simple sugar	Yes	No	No	No
pentose	Yes	No	No	No

As nouns, pentose is a hyponym of simple sugar; that is, pentose is a word with a more specific, narrower meaning than simple sugar:

simple sugar: a sugar (like sucrose or fructose) that does not hydrolyse to give other sugars; the simplest group of carbohydrates
pentose: any monosaccharide sugar containing five atoms of carbon per molecule

Other hyponyms of simple sugar include triose, tetrose, hexose, aldose, ketose, heptose.

simple sugar (noun)	pentose (noun)
a sugar (like sucrose or fructose) that does not hydrolyse to give other sugars; the simplest group of carbohydrates	any monosaccharide sugar containing five atoms of carbon per molecule